καὶ τῇ κατὰ ταὐτὰ ἐν ταὐτῷ περιαγομένῃ κινήσει πέριξ αὐτὰς ἔλαβεν ἔλαβεν
and he laid hold on them by a uniform motion going around them in the same place.
I am not sure if this is correct but αὐτὰς seems to be governed both by the prep. and the verb.
πέριξ is surely adverbial here, and ἔλαβεν needs αὐτὰς as its object. (And a word can’t simultaneously be a direct object and be dependent on a preposition.)
ok thanz, so it means something like ‘he took them from all sides’, or encompassed them.